Historically, the recommended treatment for paranasal sinus mucoceles is the complete excision of through an open approach to achieve a cure. Though with the advent of Endoscopic sinus surgery, transnasal Endoscopic sinus surgery has gained more attention in order to manage the sinus mucocele. The aim of this study is to present the efficacy of the Endoscopic marsupialization of sinus mucoceles. From 2001 to 2005, 18 patients with paranasal sinus mucoceles were treated endoscopically. This series includes 6 fronto-ethmoidal, 2 maxillary, 4 ethmoid, 2 sphenoid, and 4 middle turbinate. The presenting signs, symptoms, and radiological findings were reviewed. All patients underwent endoscopic-wide marsupialization of the mucocele; the mean follow up was 13 months. There are 10 male and 8 female subjects who were of an age range of 29-72 years. Patients were treated with endoscopic marsupialization of the mucocele. There were no recurrences in the mean 13-month follow-ups in 17(94%) of patients. Only one patient needed revision endoscopic surgery. Mucocele happens to be the most commonly benign lesion, which causes the paranasal sinus to expand. There is increasing evidence that endoscopic marsupialization of sinus mucocele results in long-term control with very low recurrence rate at or close to 0%. Thus this technique is safe and less invasive than external approaches.